Loop catching mechanism in narrow web loom



Nov. 29, 1966 E. H. JOHNSON.

LOOP CATCHING MECHANISM IN NARROW WEB LOOM Filed Feb. 18. 1965 4 Sheets-Sheet l N m R% g O E TH N O R w m N T I A E W Nov. 29, 1966 E. H. JOHNSON LOOP CATCHING MECHANISM IN NARROW WEB LOOM Filed Feb. 18, 1965 4 Sheets-Sheet 2 Nov. 29, 1966 E. H. JOHNSON LOOP CATCHING MECHANISM IN NARROW WEB LOOM 4 Sheets-Sheet 5 Filed Feb. 18, 1965 INVENTOR.

ELMER H. JOHNSON FIG.4

ATTOR NEYS Nov. 29, 1966 E. H. JOHNSON LOOP CATCHING MECHANISM IN NARROW WEB LOOM Filed Feb. 18, 1965 4 Sheets-Sheet 4 I INVENTOR. ELMER H.JOHNSON ATTORNEYS United States Patent Filed Feb. 18, 1965, Ser. No. 433,693 3 Claims, (Cl. 139118) This invention relates to improvements in narrow web looms which are capable of being successfully operated at high speeds. More particularly, the invention relates to looms of the general type illustrated in Patent No. 2,742,932, granted April 24, 1956, to Carl F. Libby, in which successive loops of weft yard are projected through the shed composed of warp yarns, each pick thus consisting of a double strand of weft yarn. The lOOps are projected through the shed by means of a finger having a small eye at its free end through which the weft yarn passes from a suitable yarn supply to the fell of the fabric which is being woven. Each time a loop of yarn is projected through the shed, the end of the loop is caught by a knitting needle which is then reciprocated to knit this loop through the previously caught loop which then is around the shank of the needle. When such a loom is operated at high speeds, vibrations are liable to occur in the swiftly moving parts so that a combination of weftlaying finger and knitting needle which may operate properly at low or moderate speeds, may be unreliable at high speeds. It is an object of this invention to construct and relate the parts of the loom in such a way that the weft loops will be reliably caught when the loom is operating at high speeds.

Another object of the invention is to provide an improved mechanism for forming an ornamental selvage on the web as it is being woven on the loom. For this purpose, a revolving weft retainer is provided at the end of the warp shed into which the weft-laying finger enters, and means are provided for moving the retainer toward or from the shed while the loom is operating, to determine the contour of the selvage at that edge of the web.

For a more complete understanding of the invention, reference may be had to the following description thereof, and to the drawings, of which- FIGURE 1 is a perspective view of mechanism embodying the invention;

FIGURE 2 is a plan view of the same;

FIGURE 3 is a fragmentary perspective view from a different angle of part of the mechanism shown in FIG- URE 1, but on a larger scale;

FIGURE 4 is an end elevation of the mechanism shown in FIGURES l and 2;

FIGURE 5 is an elevational view, on a larger scale, of the loop-catching and weft retaining parts; and

FIGURES 6 and 7 are plan views of the loop catching parts in different positions of operation.

The loom embodying the invention comprises a frame or stand having a top 10 which serves as a base for most of the parts illustrated on the drawings, the driving mechanism (not shown) being located under the top 19. The loom is provided with the customary means (not shown) for changing the shed of warp yarns. These yarns pass between dents of a reed 12 which is reciprocated toward and from the rear edge of the base 10 to beat up the picks of weft yarn W which have been inserted in the shed. A finger 14 having an eye 16 in the free end thereof is employed to thrust loops of weft yarn through the shed from the right to the left as illustrated on the drawings, the free end of the finger being the left end. In the mechanism illustrated, only one such finger is employed, all of the loops of weft yarn being inserted from the right hand side of the shed. The

finger 14 is attached at its right end to an arm 18 which is pivoted at 20, the pivot being at or near the median line of the web which is woven on the machine. The finger 14 is arcuate, the arc being substantially concentric with the pivot point 20. The arm 18 is reciprocated about its pivot by a link 22 which is pivotally attached as at 24 to the arm 18 and which extends from the arm toward the right, that is, in a direction away from the finger 14. The other end of the link 22 is pivotally attached to the pin 26 of a crank 28 which is power-driven to rotate about a vertical axis 30. To minimize vibration, the crank 28 carries a counter weight 32. The effective length of the link 22 between pivot centers 24 and 26 is preferably but not necessarily approximately equal to the diameter of the path described by the crank pin 26 around its axis 30. The back and forth movements of the finger 14 and its arm 18 are caused chiefly by the component of the circular movements of the crank pin 26 which is parallel to the line of centers between the pivots 24 and 30. This component is augmented when the finger is moving from a mid position to its extreme position to the left and back to the mid position, and is reduced when the finger is moving from the mid position to its extreme position to the right, this being due to the fact that at the mid position the long axis of the link 22 makes a considerable angle with the long axis of the crank arm. That is, the line of centers between the pivots 26 and 30. Movement that decreases this angle tends to move the finger arm toward the left;'movement increasing the angle has the opposite effect. As a result of this, when the finger 14 has been retracted from the shed, it is almost stationary while the crank is turning through an angle of well over this dwell giving the reed 12 an opportunity to beat up the newly inserted pick of weft yarn. This linkage is simple, positive and effective.

A spring 34 is attached at one end to the arm 18 and at the other end to a bracket 36 on the base 10 to prevent backlash in the linkage driving the arm 13.

The selvage at the left hand edge of the web is formed by a knitting needle 46 which is held in a horizontal position alongside of the web by a clamp 42. The type of knitting needle shown on the drawing is a latch needle having a hook 44 and a latch 46. The needle is operated to catch each loop projected through the shed by the finger 14 and to knit this loop through the previous loop caught from the finger. For this purpose the needle 40 is longitudinally reciprocated, the clamp 42 being mounted on a sleeve 48 which slides on a rod 5%) and is acuated by a link 52 connected to an arm 54 pivoted at 56 and driven by a connection with an eccentric strap 58 about an eccentric 60 which revolves with the shaft 30. The pivot 56 is carried by an adjustable bar 62 which is secured to the base 10 in adjusted position by a cap screw 64. By adjusting the position of the bar 62, the stroke of the needle 40 can be changed.

The needle 40 is located between the web which is being woven and a deflector 66 which is a part of a bracket 63 mounted on the base 10. The deflector 66 has a top edge 70 which slopes upward and forward and terminates at a recess 72 in the bracket 63. As indicated in FIGURE 3, the hook 44 of the needle 40 is located alongside of the recess '72 when the needle is at the end of its rearward stroke. The latch 46 is then open and the needle is in position to receive a loop of weft yarn from the finger 14. As indicated in FIGURE 3, the plane of the hook 44 of the needle is inclined toward the deflector 66 about 45 degrees so that the hook can readily accept a loop of left yarn from the finger 14 and can also hold this loop when the needle is drawn forward to cast off the previous loop.

The deflector 66 is an upstanding peak at the top of the bracket 68. A second such peak 74 is part of the bracket with the recess 72 between the two peaks. The peak 74 serves to prevent the latch 46 from accidental closing when the needle is stopped at the end of its rearward stroke.

When the finger is projected to the left in an arcuate path to introduce a loop of weft yarn through the shed, the eye 16 after it passes the mid point of the web has a slight forward component for the rest of the stroke. The deflector 66 is so located in relation to the extreme position of the eye 16 at the end of the stroke that the portion W; of the yarn extending from the opposite selvage to the eye of the finger rides over the sloping edge 79 and snaps into the recess 72, thus entering the hook 44 of the needle 40. As the finger is being retracted to its position to the right of the shed, the needle 40 is drawn forward to knit the loop of yarn through the previous loop which is then on the shank of the needle. The latch closes and the loop on the shank is cast off, whereupon the needle is moved back to the rear to its previous position beside the recess 72. In order to avoid clashing of the end portion of the finger with the deflector 66, the portion of the finger adjacent to the eye 16- is domed upward as at 76. This permits the eye 16 to come close to the deflector 66 as it approaches the end of its stroke toward the left.

The loom is also provided with a retainer for weft loops at the right of the shed. This is in the form of a curved rod 80 which is attached at one end to a horizontal transverse shaft 82 the axis of which is below the level of the finger 14. The curve described by the rod 80 is substantially in a plane perpendicular to the axis of the shaft 82. As indicated in FIGURE 5, the free end portion of the rod describes an approximate semi-circle which is concentric with the axis of the shaft 82. The rod may taper in cross-section toward its free end. The rotation of the shaft 82 is in timed relation to the reciprocation of the finger 14 so that some portion of the retainer 80 forms an arch over the finger while the finger is moving into and out of the shed. Thus, each time the finger carries a loop of weft yarn through the shed, the portion W of the weft from the fell of the fabric extends to the right and around the retainer 80, then to the left to the eye 16. Thus the loop 84 formed at the right selvage of the fabric is retained by the retainer 80 until clockwise rotation of the retainer, as seen in FIGURE 5, causes the retainer to move clear of the loop 84 of yarn thus formed.

To produce an ornamental selvage on the web, mechanism is provided for moving the retainer 80 gradually to the left or right during the operation of the loom so that the loops 84 will be variously spaced from the longitudinal median of the web. For example, the selvage loops 84 can be made to form a scalloped outline. For this purpose, the shaft 82 on an end of which the retainer 80 is mounted extends through an elongated bearing member 86 mounted on the base 10. A constantly rotated sprocket wheel 88 is rotatably mounted at the further end of the bearing member 86 and is driven by a chain 90 which connects it to a train of gears 92, 94 driven by a drive shaft 96. On the end of the shaft 82 remote from the retainer 80 is a block 100 carrying a fixed pin 102 which is offset from but parallel to the shaft 82. The pin 102 fits slidably in a hole through the sprocket Wheel 88 so that the shaft 82 is rotated by the sprocket wheel 88 but is also free to move axially. Axial movement of the shaft 82 and retainer is controlled by an abutting screw 104 which bears against the end of the shaft on which the block is mounted. A spring 106 which is partly housed in the bearing member 86 bears against the block 100 to press it and the shaft 82 ,yieldingly toward the abutting screw 104. This screw is adjustably carried by an arm of a lever 108 which is pivoted at 110 to a fixed bracket 112. The lever has another arm 114 carrying a cam follower 116 which is pressed against a cam 118 by the spring 106. The earn 118 is on a gear Wheel 120 which is slowly rotated by reduction gearing 122 connecting it to the drive shaft 96. The cam 118 determines the shape of the ornamental selvage formed on the right hand edge of the web by the retainer 80.

I claim:

1. In a narrow-web loom having a frame and warp shed-forming means carried thereby, means for projecting successive loops of weft yarn through said shed from one side thereof to the other, said means comprising an arm pivoted at one end to said frame, a weft-laying finger secured to the free end of said arm, said finger having an arcuate shape concentric with said pivot point, a power-driven crank mounted on said frame, and a link pivotally attached at one end to said arm at an intermediate point thereof and at the other end to said crank, the effective length of said link being approximately equal to the diamenter of the circular path described by the rotation of said crank.

2. In a narrow-web loom having a frame and warp shed-forming means carried thereby a weft laying finger mounted on said frame for reciprocating movement into and out of said shed, said finger having a free end with an eye therein adapted to enter the warp shed at one side thereof and be thrust through to a point beyond the far side thereof and then be retracted to the side of entry, a horizontal transverse rotatable shaft mounted on said frame at a level a little below that of said finger and with an end thereof adjacent to the entry side of the shed, a weft yarn retainer carried by said shaft, said retainer comprising a curved rod attached at one end to said shaft, the free end portion of said rod forming an approximately semi-circular loop concentric with and in a plane perpendicular to the axis of said shaft, the rotation of said shaft and retainer being timed so that the weft yarn from the fell of the fabric passes around said retainer to said eye when said linger is moving through the shed to the far side.

3. Mechanism as described in claim 2, and means for moving said shaft axially during the rotation thereof with said retainer, whereby to vary the distances of the weft loops on the side of entry from the median of the web which is being woven.

References Cited by the Examiner UNITED STATES PATENTS 2,180,832 11/1939 Libby 139-124.1 2,208,886 7/1940 Vorck 139124.1 2,236,325 3/1941 Vorck 139124.1 2,742,932 4/ 1956 Libby 139l24.1 2,902,057 9/1959 Turner l39-124 MERVIN STEIN, Primary Examiner.

H. S. JAUDON, Assistant Examiner. 

1. IN A NARROW-WEB LOOM HAVING A FRAME AND WARP SHED-FORMING MEANS CARRIED THEREBY, MEANS FOR PROJECTING SUCCESSIVE LOOPS OF WEFT YARN THROUGH SAID SHED FROM ONE SIDE THEREOF TO THE OTHER, SAID MEANS COMPRISING AN ARM PIVOTED AT ONE END SAID FRAME, A WEFT-LAYING FINGER SECURED TO THE FREE END OF SAID, SAID FINGER HAVING AN ARCUATE SHAPE CONCENTRIC WITH SAID PIVOT POINT, A POWER-DRIVEN CRANK MOUNTED ON SAID FRAME, AND A LINK PIVOTALLY ATTACHED AT ONE END TO SAID ARM AT AN INTERMEDIATE POINT THEREOF AND AT THE OTHER END TO SAID CRANK, 